Exhaust-valve-actuating means for internal-combustion engines.



J. A. BROWN.

EXHAUST VALVE ACTUAIING MEANS FOR INTERNAL COMBUSTION ENGINES. APPLICATION FILED MAR. 8, 19m

1,261,355.. Patented Apr. 2, 1918.

Inventor, JA.Brown, 6g

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JAMES A. BROWN, OF CEDAR RAPIDS, IOWA. ASSIGNOR TO PERFECTION GAS ENGINE COMPANY, OF CEDAR RAPIDS, IOWA,'A CORPORATION OF SOUTH DAKOTA.

Specification of Letters Patent.

Patented Apr. 2, 19118.

Application filed March 8, 1917. Serial No. 153,439.

To all whom it may concern:

Be it known that I, JAMES A. BROWN, a citizen of the United States of America, and a resident of Cedar Rapids, Linn county, Iowa, have invented certain new and useful Improvements in Exhaust-Valve-Actuating Means for Internal-Combustion Engines, of which the following is a specification.

My invention relates to improvements in exhaust-valve actuating means for internal combustion engines wherein said valve actuating means is operated alone by employing a portion of the exhausted gases arising from combustion of the fuel consumed in the combustion chamber of an engine, and the object of my improvement is to automatically control the action of said valve-actuating device by means of suitable connecting mechanism between said device and the speed regulating device of the engine.

This object I have accomplished by the means which are hereinafter described and claimed, and which are illustrated-in the accompanying drawings, in which Figure 1 is a side elevation, in partial section of an internal combustion engine supplied with my improved exhaust-valve actuating means and with my mechanism for controlling the latter automatically, with parts broken away; Fig. 2 is a detail plan view of the connecting mechanism between the engine governor and the tripping or releasing elements of the exhaustvalve actuatingmeans, with parts broken or sectioned away, and Fig. 3 is a detail enlarged elevation, taken at an angle of 90 degrees to the view shown in said Fig. 1, of said tripping or releasing mechanism for the exhaustvalve. Fig. 4 is a perspective view of the same mechanism.

Similar numerals of reference denote corresponding parts throughout the. several views.

I have shown my improved exhaust-valve stationar engine mounted on a fixed support 35, ut it is obvious that said mechanism may be used on any other type of internal combustion engine without departing from the principle of my invention.

The engine cylinder 5 contains the usual reciprocatory piston 6 having a pitman pivotally connected between it and the crankpin of a crank-shaft 29 rotatably mounted in bearings (not shown) on the frame 35,

and which may have thereon the usual flywheel, not shown.

The numeral 1 denotes a vertically disposed auxiliary cylinder mounted on the cylinder-head of said engine, and having in its upper removablehead an inlet-port 2 in communication by means of -a conduit 3, With an auxiliary exhaust-port 4 in the engine-cylinder 5. The cylinder 1 has divisional partitions 20 and 34, of which the former is provided with a centrally located seat for the exhaust-valve 21 spaced from the lower head 11, and the latter with a central orifice through which the stem 8 of said valve extends upwardly into a chamber 36 containing a reciprocatory piston 7 above the upper end of said stem. Within the chamber 36 and under said piston 7, a standard 12 projects upwardly fixedly from the partition 34. This standard has a pair of spaced lateral lugs 15 between which is medially pivotally mounted an oscillatory lever 13 having a detent 26 at its upper end.

The numeral 9- denotes a fixed arm on the upper part of the valve stem 8, having an acutely angled upper edge to fit under the hooked detent 26 on the lever 13, and a coiled compression-spring 10 encircles said stem, and is adapted to normally propel said stem 8 upwardly to keep the exhaust-valve 21 closed against its seat.

The numeral 16 denotes a bell-crank lever medially pivoted upon the partition 34 and having one end normally in engagement with a beveled art 25 of the lower end of 15? lever 13 to old the latter upright fixyi A standard 27 extends upwardly from the partition 34 and carries at its upper end a lateral plate-spring 28 whose free end engages the arm 9 and is adapted to retain thelatter yieldingly in its seat when engaged with the detent 26 of the oscillatory lever 13. The lower part of said lever is beveled away at the back to permit it to rock freely when released by the engaging device now to be described.

Referring to Figs. 2 and 4, a bell-crank lever 16 is mounted to rock on a pivot-stud on the partition 34, and has one end formed to engage the beveled ofi angle 25 of the lower end of said lever 13, and is held in yielding engagement therewith by a spring 17 mount ed on said pivot-stud and which engages the opposite end of said bell-crank lever.

On the crank-sl1aft 29 is fixed a sleeve 31 on which is mounted a slida-ble rotatable terminally-flanged spool 30. Said sleeve hasoppositely-directed pairs of fixed arms 32 between which are pivoted a pair of governor-weights 33 having fingers inturned to pass movably'between the flanges of said spool. A lever 18 is medially pivoted between lugs 19 on the engine-casing, and has one end positioned movably between the flanges of said spool. Its other end is bent and passed through an opening 37 in the cylinder 1 and engages with the outer end of the bell-crank lever 16.

A chamber 38 in the cylinder 1 below the partition 20 opens by means of a relatively large port into the combustion chamber of the cylinder 5. On the lower face of the relatively large exhaust-valve 21 is an cecentric stud 22. On the adjacent face of the engine-piston 6 is a tappet-pin 23 in line with the stud 22.

Operation:

The exhaust-valve 21 being closed against its seat, the auxiliary piston 7 in its uppermost position, and the engine piston 6 having receded on its power-stroke to uncover the auxiliary exhaust-port 4, a portion of the burnt gases of combustion rush through said port, the conduit 3, and the port 2 into the chamber 36 of the cylinder 1, forcing down the piston 7, which in turn, pushes down the stem 8 against the tension of the spring 10 and forces open the exhaust-valve 21. The fixed arm 9 on said valve-stem moves down along the upper end of the trigger 13, and is caused by the pressure of the spring 28 to pass into the notch thereon and become interlocked with the detent 26 thereon to hold the exhaust-valve open.

When the engine piston 6 returns, the tappet pin 23 thereon passes through the opening in the cylinder-head, engages with the eccentric pin 22 on the exhaust-valve 21 and rocks said valve and its stem enough to disengage the arm 9 from the hooked detent 26 of the lever 13, the spring 10 yielding downwardly and torsionally as the bevel of the arm slides over the bevel of the detent,

thus permitting the spring 10 to push said end of the latter to move away from the bell-crank lever 16, releasing the latter so that it can rock freely on its pivot and be kept in contact with the lever 13 which may swing freely to and fro, and the acutelyangled arm 9 cannot become disengaged while so swinging from under the hooked detent 26 being held therein by the spring 28, whereby the exhaust-valve 21 is held open until the speed of the engine has become reduced to the normal.

By the above means, the action of the exhaust valve actuating means is automatically regulated. The lever 18 may be used in connection with any other form of governor mechanism desired, and the connections between the governor and said oscillatory lever 13 may also be varied in their elements,

their forms, or proportions, without departing from my invention. a

It will be Seen that by the use of my device, a very large exhaust-valve and exhaust passages may be employed whereby the combustion chamber may be quickly scavenged, thus instantaneously and completely releasing the heated gases resulting from combustion of the fuel, which keeps down the temperature in the combustion chamber, and also saves power which might otherwise be lost on the return stroke of the piston because of compression of gases not otherwise completely driven out of the combustionchamber.

Having described my invention, what I claim as new, and desire to secure by Letters Patent, is:

1. In an internal combustion engine, in combination, mechanism actuated solely by pressure of a portion of the exhaust gases for opening the main exhaust-valve, including a separable. locking-device containing a swinging element adapted to hold the exhaustvalve open and yieldable resilient means to hold said element locked while permitting it to swing freely, means operable by the engine at a certain point in the cycle thereof to unlock said locking-device, a resilient connection adapted to return said exhaustvalve when unlocked to its closed position, a speed-governor actuated by the engine, and a lever rocked by said speed-governor into or out of engagement with said swinging element, retaining the latter when engaged therewith in one position against the tension of said yieldable resilient means to permit said engine-operated means to unlock said locking-device releasing the exhaust valve to be closed by said resilient-connection.

2. In an'internal combustion engine, in combination, mechanism actuated solely by pressure of a portion of the exhaust gases for opening the .main exhaust-valve, includ ing a separable locking-device containing a swinging element adapted to hold the exhaust-valve open and yieldable resilient means to hold said element locked while permitting it to swing freely, means operable by the engine at a certain point in the cycle thereof to unlock said locking-device, a resilient connection adapted to return said exhaust-valve when unlocked to its closed position, and means movable into or out of engagement with said swinging element, retaining the latter when engaged therewith against the tension of said yieldable resilient means to permit said engine-operated means only at that time to unlock said locking-device releasing the exhaust-valve to be closed by said resilient connection,

Signed at Cedar Rapids, 1a., this 2d day of March, 1917.

JAMES A. BROWN. 

